fixup! Fallback to directory icon based on the mount type

Author: juliusknorr

core/js/dist/share_backend.js

@@ -275,7 +275,7 @@ OC.Share = _.extend(OC.Share || {}, {
 		action.removeClass('shared-style');
 		// update folder icon
 		if (type === 'dir' && (hasShares || hasLink || ownerId)) {
-			if (mountType !== 'shared-root' && mountType !== 'shared') {
+			if (typeof mountType !== 'undefined' && mountType !== 'shared-root' && mountType !== 'shared') {
 				shareFolderIcon = OC.MimeType.getIconUrl('dir-' + mountType);
 			} else if (hasLink) {
 				shareFolderIcon = OC.MimeType.getIconUrl('dir-public');